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 ###Instrução: Em que data está a equipe vencedora Abt Sportsline e a pole position de Mattias Ekström no Circuito Ricardo Tormo, Valencia?
 ###Tabelas: CREATE TABLE in-plane_switching_ips (in-plane_switching_ips_id AUTO_INCREMENT PRIMARY KEY, Name VARCHAR, Nickname VARCHAR, Year INT, Advantage VARCHAR, Transmittance/ contrast ratio VARCHAR) CREATE TABLE race_calendar_and_results (race_calendar_and_results_id AUTO_INCREMENT PRIMARY KEY, Round VARCHAR, Circuit VARCHAR, Date VARCHAR, Pole Position VARCHAR, Fastest Lap VARCHAR, Winning Driver VARCHAR, Winning Team VARCHAR) CREATE TABLE champions_and_top_goalscorers (champions_and_top_goalscorers_id AUTO_INCREMENT PRIMARY KEY, Season VARCHAR, Champion VARCHAR, Runner-Up VARCHAR, 3rd Position VARCHAR, Top Goalscorer(s) VARCHAR, Team(s) INT) CREATE TABLE 4-8-4 (4-8-4_id AUTO_INCREMENT PRIMARY KEY, Class VARCHAR, Wheel arrangement VARCHAR, Fleet number(s) VARCHAR, Manufacturer VARCHAR, Serial numbers VARCHAR, Year made VARCHAR, Quantity made VARCHAR, Quantity preserved VARCHAR, Year(s) retired VARCHAR) CREATE TABLE singles:_18_12–6 (singles:_18_12–6_id AUTO_INCREMENT PRIMARY KEY, Outcome VARCHAR, Date VARCHAR, Tournament VARCHAR, Surface VARCHAR, Opponent VARCHAR, Score VARCHAR)  
SELECT Date FROM race_calendar_and_results WHERE Winning Team = Abt Sportsline AND Pole Position = Mattias Ekström AND Circuit = Circuit Ricardo Tormo , Valencia